I would suggest that the term "non-Jew" is both precise and neutral, and a perfectly acceptable halachic term as well, as halachic works such as the Shulchan Aruch often refer to א"י or אינו יהודי (non Jew).

I think that if people are talking in English, then the words "gentile" or "non-Jew" should be used. However, the terms gentile and non-Jew are likely to be inappropriate if the if the conversation is in more of a "Yeshivish" dialect, because these are both English words. How about Nokhrim (נכרים) or Zarim (זרים)? The latter terms both mean something along the lines of aliens or strangers.

How is it "inappropriate" to use sufficiently descriptive English words in an English conversation that happens to be in a "Yeshivish" context? Given that Yeshivish is entirely a folk dialect, I don't get how prescriptivism makes any sense with respect to it.
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Isaac MosesJun 25 '12 at 14:23